Double-color mechanical pencil or sharp pencil



April 1s, 1933. T. YAMASHIIA'TA DOUBLE coma uEcHANIcAL PENCIL QR swr PENCIL 2 sheets-sheet i med march, ze, lesa' ATTORNEYS.

vApril 18, v1933- 1 T. YAMAsl-.n'rA Y 1,903,800

DOUBLE coton MECHANICAL-mwen 0R SHARP PENCIL Filed March 2s,- 1952 2 sheets-sheet 2 IN VEN TOR.

ATTORNEYS.

Emma paraisse l PATE-N1" ori-*ica 'l'.mBHIT-A, 0l' XOIQSHIXA'WA-XU, TOXYQ.

DOUBLE-COLOR HECHANICAL PENCIL B SHARP-mm Application med Iaroh 28,1988, Serial lo. 801,630, and in AJapaxi August 28, 1931.

This invention relates to a double-color mechanical pencil or shar ncil, and consists of a barrel a tubular riving screw having crossin helical grooves on the inner surface thereo a guide-and-magazine -unit made from one blank cut from a sheet metal and having two semi-cylindrical leadmagazines and two guide channels, two lead propelling members mounted in said guide c annels in the guide-and-magazine unit and each carrying a lead and a resilient ven aging member engaging with said crossing elical grooves on the tubular driving screw, and parts being arranged in such manner that two leads may be propelled alternately by rotating the said guide-and-magazinc unit in one direction or the other. Y

One ob'ect of the invention is to provide 'a novel s arp pencil containin black and red i1leads which can be alterna y propelled ,eas

Another object of the invention is to rovide such double-color sliar (pencil w ich can be manufactured, assem le and disassembled by most simple operations, and is most durable.

In the accompanying drawings, illustrating what I now consider the preferred form of this invention,

Fi 1 is a central sectional view through a pencil constructed according'to this invention l Fig. 2 is a central sectional view taken at a right angle to Fig. 1; Fig.- 3 is a cross section on line III-'III of Fig. 1;

Figs. 4 and 5 are elevations of the lead propelling opposte Sides;

Figs. 6 and 7 are longitudinal sectional views of the members shown in Figs. 4 and 5, at right angles thereto;

Figs. 8 and 9 are, respect1vely, a front ele- 4.5 vation and a side elevation the latter being partly in section of a double guide bar with lead magazines;

Figs. 10 and 11 are elevations showing the" method of manufacturing the double guide bar with lead magazine; Fig. 11 showing a members viewed respectively, from dat blank, and Fig. 10 showing a half made double guide bar with lead magazines.

Fig. 12 is a cross section on the line 12-12 of F1g. 13; f

Fig. 13 is an elevation of an eraser holder; Fig. 14 is a cross section on the line 14-11 of F1g. 9;

Fig. 15 is a cross section on the line 15--15 of F1g. 9;

Fig. 16-is a cross section on the line 16-16. According to this invention, two guide bars A, A and two lead magazines B, B are made in one piece from a b ank cut from a sheet metal as showii in Fi 11. The -blank is bent along two longitu inal chain lines, thus forming guide channels A, A and two semicylindrical portions B, B at opposite ends as vshown in Fig. 10 at the left and side of Fig. 11. Then, it is bent at the mid point with the guide channels A facin outwardly, as shown in Figs. 8 and 9. Wien cutting the blank tongues 1, 1 are cut out, and, they are bentv at right angle so as to form bottoms o f respective lead magazines as best shown in Figs. 1 and 2. .On the lead magazine B, B 75 grooves b, b are formed so as to constitute an annular groove when the magazines are brought together. At the upper ends of the lead magazines B, B recesses 2, 2 are formed to receive therein an eraser holder C. Said eraser holder C is rovided at diametricall opposite sides with ongitudinal slots 4 whic are vada ted to engage with and ip the inwardly nt portions 3, 3 of the Ycad. magazines, whereby said two semi-cylindrical lead megazines are firmly held together. l n each of the guide channels formed on the opposite sides of the guide bar A a lead ro elling member D is slidably mounted. ai -lead propelling member D has a stiif- 'ening indentation or embossment 5 and has an upper bent portion 6 which is provided with an engag'liplg ridge 7. Said engaging ridge 7 is inc ed andvresiliently'en with one of crossing helical ves formed on the inner side lof the driving screw E. To the other end of ealiropelling member D is secured a flexible 8 preferably consisting of a wire rope, whic carries at its lower end a leadl holder d. In said lead 10 `in the guide bar A.

holder d is provided a usual means for discharging remaining short lead from the holder The tubular driving screw member 1s formed of a sheet metal worked by pressing and rolling operation, and it has crossing helical grooves e on the inner surface thereof. Such crossing helical grooves e are shown as crossing helical ridges on the outer surface of the driving member. Near the upper end, the driving screw member E is provided on the inner surface with an annular ridge or projection 9, and there are formed longitudinal slits 10 10 diametrically opposite to each other. W ien the guide-and-magazine unit A, is inserted into the tubular driving screw E, the ennuiar grooves b is engaged by the annular ridge 9. At the lower end of the driving screw E, a hole 11 is formed, which receives s. projection 12 formed on a coupling tube Said coupling tube F is provided with a male screw thread f on its lower end which protrude be ond the lower end of the barrel G, and to w ich screw thread is screwed a nozzle or end section H. 13 designates a cap carrying a clip 14. 15 is an india-rubber eraser. The leeds are designated by 16, 16.

Accordin to this invention, by removin the end section H all inner parts can be rea ily detached. For assembling the parte, the eraser holder C is inserted in the upper end of the guide-and-magazine unit A, B with the slits 4, et enga ing the bent portion 3 on the ma azine. Fllgwo lead propellin members D, are mounted in the uide c annels Then t e guide-andmagazine unit A, B is inserted intothe tubular driving screw E, with the annular groove b engaged by the inner annular ridge 9 on the tubular driving screw E. The joint tube F is screwed to the lower end of the tubular driving screw E, and the whole is inserted into the barrel G. Then, by screwing the end section H on the lower end of the joint tube F which rotrudes beyond the members D, D will proceed while the other recedes. Thus, one may alternately use the desired one of the leads.

Inasmuch as two lead magazines and two guide bars are made from a one piece blank cut from sheet metal, the manufacture thereof is most simple. The parts being assembled by groove-and-ridge connection and by hole-and-projection connection, not using any solder or any other uniting means, the parts may be disassembled easily, .and breakage may be reduced to a minimim. Inasmuch as the en 'a rid e 7 of the lead prollin membe lglylflildinggly engage with the elica groove `e on the riving screw E on account of the resiliency of the bent portion 6, and said resiliency is limited by the embossment or indentation 5, which, being in -the nature of a corrugation, stiffens the part and as the lead holder d is carried by a flexible rod 8, a soft and reliable action can be expected in propelling the leads, and breakage of the leads is reduced to minimum.

What I claim is:

1. 1n a double-color sharp pencil, a guideand-magazine unit made Jroin one blank cut from a sheet metal and havin two semic lindrical lead magazines an two guide c annels, lead ropelling members respectively mounted in said guide channels, and a tubular driving screw having crossing belical grooves engaging with said lead propelling members. A

2. In a double-color sharp pencil, a guideand-magazine unit made from one blank cut from a sheet metal and having two semicylindrical lead magazines provided with an annular groove and two guide channels, lead propelling members respectively mounted in said guide channels, a tubular driving screw having crossing helical grooves engaging with said lead propelling members and having an inner annular rid e engaging with said annular groove on t e magazines, and means for holding said two semi-cylindrical lead magazines together.

3. ln a double-color shar pencil, a barrel, a tubular driving screw liaving near one end a hole, a guide-and-magazine unit inserted in said tubular driving screw, a coupling tube havin a projection engaged by said hole in the riving screw, and a nozzle screwed on the free end of the said joint tube protruding from the barrel.

4. In a double-color sharp pencil, a barrel, a tubular driving screw having near one end a hole, a guide-and-magazine unit made in one piece havin two uide channels and inserted in said tu ular riving screw, lead propelling members mounted in said guide channels, a couplin tube having a projection engaged by said hole in the driving screw, and a nozzle screwed on the free end oflsaid joint tube protruding from the barre v 5. In a double-color sharp pencil, a guideand-magazine `unit made from one blank cut from a sheet metal and having two semic lindrical lead magazines and two guide channels, andan eraser holder having two longitudinal slits adapted to grip the said two semi-cyclindrical lead magazines together.

6. In a double-color sharp pencil, two vlead propelling members each having a stop and an upper resilient bent portion carrying an inclined engaging ridge, and a tubular driv- .o 7. In doubl-color cil, a lud Folder, a le'lad propelling em r, s flexible x iconsisting ofmwil'erov andconn s: :d lead.` propelling mem r 'and the h\ lder, and menus for dischar the ne- 10 maining short lead' from said lead older.

In testimony whereof I ax my signo.-

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